Longwall Equipment Having Vertically Adjustable Disc Shearer Loader Guided on the Face Conveyor

ABSTRACT

Longwall equipment for mechanical extraction, especially in underground coal mining, including a face conveyor disposed along a longwall face, a disc shearer loader that includes a machine body that rests, and is guided, upon the face conveyor and includes two shearing discs pivotably disposed thereon, with the machine body extending over the face conveyor and forming a portal that prescribes a maximum loading cross-section of the face conveyor, a lifting mechanism mounted on the machine body for guiding it on the face conveyor in a vertically adjustable manner and for variably adjusting the portal cross-section, a drive element height-adjustably disposed on the machine body and engaging an abutment fixedly disposed on the face conveyor, and shield support units that include top canopies that project toward the disc shearer loader.

The present invention relates to longwall equipment for mechanical extraction, in particular in underground coal mining, with a face conveyor disposed along the longwall face, with a disc shearer loader displaceable on the face conveyor, and with shield support units disposed at an angle relative to the face conveyor and having top canopies that project toward the disc shearer loader, whereby the disc shearer loader is provided with a machine body that rest, and is guided, upon the face conveyor and that includes two shearing discs that are pivotably disposed on the machine body, and the machine body, which extends over the face conveyor, forms a portal that prescribes the maximum loading cross-section of the face conveyor.

To the extent that longwall equipment of this type is known through use, there is a particular problem in that during the so-called ascent of the disc shearer loader, in other words during the extraction travel counter to the conveying direction of the face conveyor, the material extracted by the shearing disc that leads the machine body, and cuts in the region of the top canopy, must be conveyed away through the portal formed by the machine body over the face conveyor. In this connection, it should be noted that the leading shearing disc cuts the predominant portion of the face height that on the whole is cut loose by the disc shearer loader, and loads it on the face conveyor. In this connection, the portion cut by the leading shearing disc increases with a disc diameter that increases in relation to the seam thickness, or with an increasing spacing of the guidance of the cut of the leading shearing disc from the top canopy, due to the gob associated or intended therewith, as well as generally as the seam thickness decreases. Thus, with shearing disc operations in coal seams having a thickness of about 2 m to 2.5 m, the leading shearing disc has an extraction yield of about 75% to 90% of the seam thickness. Due to this circumstance, during the ascent of the disc shearer loader, the removal of the extracted material through the portal of the disc shearer loader can become a capacity-limiting factor.

It is therefore an object of the present invention to provide longwall equipment of the aforementioned general type where the disc shearer loader itself forms no direct limitation for the establishment of its recovery yield.

The realization of this object, including advantageous embodiments of the invention, result from the contents of the patent claims, which follow this description.

The basic concept of the present invention is that the machine body of the disc shearer loader, for the variable adjustment of its portal cross-section by means of a lifting mechanism mounted on the machine body, is guided on the face conveyor in a vertically adjustable manner, and the drive element, which is disposed on the machine body and engages in an abutment that is fixedly formed on the face conveyor, is adjustable in height on the machine body.

The present invention primarily has the advantage that due to an adjustment of the maximum possible portal cross-section by raising the machine body of the disc shearer loader relative to the face conveyor, the extraction yield during ascent of the disc shearer loader can be increased. Consequently, the extraction yield of the disc shearer loader can be more easily adapted to changing seam thicknesses.

Furthermore, the possible alteration of the vertical position of the machine body of the disc shearer loader that runs upon the face conveyor results, in conjunction with the disc support arms that are pivotably mounted on the machine body, in an even greater clearance or margin when traveling through face portions having a correspondingly lesser or even greater thickness, because due to the alteration of the vertical position of the machine body, the face height that is to be cut loose is to be reduced or increased beyond the range or reach of the disc supporting arms that are disposed on the machine body with a structurally fixed pivot angle.

A comparable advantage also results with a curved face, for example if in the direction of travel of the disc shearer loader, or transverse to the direction of extraction, depressions or saddles are defined in the seam. Since presently known disc shearer loaders, due to their installed capacity, can be made relatively long and can reach an overall length of, for example, up to just about 10 m, when conventional disc shearer loaders pass through saddles or depressions, it can happen that a greater face height must be cut loose than what the seam thickness corresponds to in order to provide an adequate passage height for the disc shearer loader below the top canopies of the shield support units. Also in such cases is the height adjustability of the machine body of the disc shearer loader pursuant to the present invention helpful in being able to travel through such narrow locations in a more reliable manner and at a lower level of a cutting loose of the face height, because appropriate height reserves can be mobilized at the corresponding low positions of the face by lowering the machine body of the disc shearer loader.

In this connection, it is to be understood that during normal extraction operation, alterations in the vertical position of the machine body relative to the face conveyor can be compensated for by a synchronous adaptation of the position of the disc supporting arms for the adaptation of the portal cross-section in order in just a normal extraction operation not to alter the cutting height of the shearing discs or the overall cut-free or loose face height.

Pursuant to one specific embodiment of the invention, the machine body can be adjustable in height in an infinitely variable manner. The machine body could also be adjustable in height during the travel of the disc shearer loader so that no time is lost during the extraction operation.

Pursuant to another embodiment, both the coal face side as well as the extraction side of the machine body can be adjustable in height in a respectively separate manner from one another. Thus, it is possible to individually adjust the height of the two sides of the machine body, so that even during the advancement of the disc shear loader, both of its sides can be individually adjusted. This is particularly helpful when maneuvering for traveling through narrow locations, especially saddles or depressions.

Pursuant to other specific embodiments of the present invention, the lifting mechanism for the machine body can be provided with hydraulic drive elements, or even with electromechanically operating drive elements, for example utilizing servo motors and gear mechanisms.

Pursuant to a first specific embodiment of the invention, the lifting mechanism for the machine body can be comprised of vertically disposed lifting cylinders that are supported on the face conveyor.

Alternatively, the lifting mechanism can be comprised of two eccentric drives that are spaced apart on the machine body, are respectively acted upon by horizontally disposed lifting cylinders, and are supported on the face conveyor.

With respect to an operationally reliable control of the extraction work, pursuant to one exemplary embodiment of the present invention, the lifting cylinder can be equipped with a displacement measuring system for the control of the vertical position of the machine body on the face conveyor.

Pursuant to another specific embodiment of the invention, the control of the extraction work can be further improved by providing a device for measuring the distance between the bottom edge of the top canopy of the shield support units and the upper surface of the machine body.

Exemplary embodiments of the invention are shown in the drawings and will be described subsequently. In the drawings:

FIG. 1 is a schematic side view of longwall equipment with face conveyor, disc shearer loader, and shield support unit,

FIG. 2 shows the subject matter of FIG. 1 while traveling through a lesser (left illustration) seam thickness and a greater (right illustration) seam thickness,

FIG. 3 is a schematic illustration of an embodiment of the lifting mechanism for the machine body of a disc shearer loader.

The longwall equipment illustrated in FIG. 1 primarily includes a shield support frame 10 having a floor skid 11 on which are placed two props 12, which are arranged parallel to one another, with only one prop being recognizable in FIG. 1; at their upper ends, the props support a top canopy 13. While the front (left) end of the top canopy 13 projects in the direction of the extraction machine, which will be described below, a gob shield 14 is pivotably connected to the rear, right end of the top canopy 13 by means of a joint 15, whereby the gob shield 14, as can be seen from the illustrated side view, is supported by two supporting connection rods 16, which rest upon the floor skid 11. Three inclination sensors 17 are disposed on the shield support frame 10, and in particular one inclination 17 on the floor skid 11, one inclination sensor 17 in the rear portion of the top canopy 13 in the vicinity of the joint 15, and one inclination sensor 17 on the gob shield 14. The inclination sensors can be used to control the extraction work of the longwall equipment illustrated in FIG. 1, with such control not being the subject matter of the present application.

The shield support frame 10 illustrated in FIG. 1 is attached to a face conveyor 20, whereby an extraction machine, in the form of a disc shearer loader 21 having an upper shearing disc 22 and a lower shearing disc 23, is guided on the face conveyor 20. Each of the two shearing discs 22, 23 is held by disc supporting arms 24 that are pivotably disposed on the machine body 25. The machine body 25, in a non-illustrated manner, rests not only on that side of the face conveyor 20 that faces the shearing discs 22, 23, but also on that side of the face conveyor that faces away from the shearing discs, so that the machine body 25 extends over the face conveyor 20 at a distance, forming a so-called portal 26 that delimits the loading cross-section of the face conveyor 20, especially during ascent of the disc shearer loader.

To make the cross-section of the portal 26 variably adjustable, indicated merely schematically in the exemplary embodiment of FIG. 1 are vertically disposed lifting cylinders 27, by means of which the vertical position of the machine body 25 of the disc shearer loader 21 can be varied relative to the face conveyor 20. Furthermore, a sensor 28 is additionally disposed in the vicinity of that surface of the machine body 25 that faces the top canopy 13 of the shield support frame; this sensor serves for the measurement of the spacing between the machine body 25 and the top canopy 13. With the aid of such a sensor, the position of the machine body 25 in relationship to the top canopy 13 of the shield support frame 10 can be monitored. On the one hand, changing seam or stratum thicknesses can lead to different vertical or height positions of the top canopy 13 of the shield support frame 10 in different longwall portions; on the other hand, when the longwall operation is shut down for a longer period of time, a lowering of the respective top canopy 13 of shield support frames 10 caused by convergence can occur, so that it is possible by means of the sensor 28 to respectively determine if, due to a free vertical clearance that has been determined between the face conveyor 20 and the top canopy 13, an adaptation of the vertical height of the machine body 25 of the disc shearer loader 21 must be effected.

As illustrated in greater detail in FIG. 2, the vertical position of the machine body 25 relative to the face conveyor 20 can be adapted at different seam or stratum thicknesses in order to ensure a free passage of the disc shearer loader 21, with its machine body 25, between the face conveyor 20, which is disposed on the footwall 31, and the top canopy 13 of the shield support frame 10, which rests against the roof or overlying stratum 30, accompanied by a respective maximum adjustment of the free cross-section of the portal 26. In this connection, the two shearing discs 22 and 23 are respectively in engagement with the coal front or face 32.

Within the framework of a structural realization of the present invention, the height-adjustable travel mechanism of the disc shearer loader 21 is to be constructed in such a way on the face conveyor 20 that in addition to a high mechanical stability, in particular also of the lifting mechanism, the cross-section of the portal 26 is not to be limited due to the structural configuration of the machine body 25 with lifting mechanism. Likewise, a robust design of the drive elements that are to be disposed on the machine body 25 in a height-variable manner is to be taken into consideration.

FIG. 3, in a merely exemplary schematic illustration, shows an appropriate concept for the construction of such a lifting mechanism. Here, each of the two outer ends of the machine body 25 is provided with an eccentric drive 38, the pivoting movement of which, which is controlled via a horizontally disposed lifting cylinder 37, leads to an alteration of the support of a support member 38 a upon a support element 35 that is fixedly mounted on the face conveyor 21. To this extent, by actuating the lifting cylinder 37, which is preferably equipped with a displacement measurement system, a different vertical position of the machine body 25 relative to the support element 35 that is fixedly mounted on the face conveyor 20 can be established. In so doing, at the same time care must be taken that the drive element disposed on the machine body 25 respectively also remains in engagement with a rail arm 36, as an abutment for the drive movement of the disc shearer loader 21, and which is fixedly disposed on the face conveyor 20. In the illustrated embodiment, this drive element is embodied as a drive gear or pinion 39 that is fixedly mounted on the machine body 25 and that is in meshing engagement with a drive gear 40, which is mounted on the machine body so as to be adjustable in height by means of a pivotably mounted connecting arm 41, and which in turn establishes a constant engagement with the rail arm 36 of the face conveyor 20. The possible pivot movement of the height-adjustable drive gear 40 is indicated by the line 42. Such an arrangement ensures that independently of the respective vertical position of the machine body 25 relative to the face conveyor 20, the two drive gears 39, 40 are respectively in engagement with the rail arm 36.

The features of the subject matter of these documents disclosed in the preceding description, the patent claims, the abstract and the drawings can be important individually as well as in any desired combination with one another for realizing the various embodiments of the present invention. 

1-10. (canceled)
 11. Longwall equipment for mechanical extraction, for example in underground coal mining, comprising: a face conveyor adapted to be disposed along a longwall face; a disc shearer loader that is displaceable on said face conveyor, wherein said disc shearer loader includes a machine body that rests, and is guided, upon said face conveyor, further wherein said machine body includes two shearing discs that are pivotably disposed on said machine body , and wherein said machine body extends over said face conveyor and forms a portal that prescribes a maximum loading cross-section of said face conveyor; a lifting mechanism mounted on said machine body for guiding said machine body on said face conveyor in a vertically adjustable manner and for variably adjusting the portal cross section; an abutment fixedly disposed on said face conveyor; a drive element disposed on said machine body, wherein said drive element is adjustable in height, and wherein said drive element engages said abutment; and shield support units disposed at an angle relative to said face conveyor, wherein each of said shield support units includes a top canopy that projects toward said disc shearer loader.
 12. Longwall equipment according to claim 11, wherein said machine body is adjustable in height in an infinitely variable manner.
 13. Longwall equipment according to claim 11, wherein said machine body is adjustable in height during travel of said disc shearer loader.
 14. Longwall equipment according to claim 11, wherein both a coal face side as well as an extraction side of said machine body are adjustable in height in a respectively separate manner from one another.
 15. Longwall equipment according to claim 11, wherein said lifting mechanism for said machine body is provided with hydraulic drive elements.
 16. Longwall equipment according to claim 11, wherein said lifting mechanism for said machine body is provided with electromechanically operating drive elements.
 17. Longwall equipment according to claim 17, wherein said lifting mechanism for said machine body is comprised of vertically disposed lifting cylinders that are supported on said face conveyor.
 18. Longwall equipment according to claim 11, wherein said lifting mechanism is comprised of two eccentric drives that are spaced-apart on said machine body and are supported on said face conveyor , and wherein horizontally disposed lifting cylinders are provided for respectively acting on said eccentric drives.
 19. Longwall equipment according to claim 17, wherein said lifting cylinders are equipped with a displacement measuring system for control of the vertical position of said machine body on said face conveyor.
 20. Longwall equipment according to claim 18, wherein said lifting cylinders are equipped with a displacement measuring system for control of the vertical position of said machine body on said face conveyor.
 21. Longwall equipment according to claim 11, which includes a device (28) for measuring a distance between a bottom edge of said top canopies of said shield support units and an upper surface of said machine body. 